Improvement in boiler-furnaces



UNITED STATES PATENT OFFICE.

THOMAS B. DAVIS, OF BOSTON, MASSACHUSETTS, ASSlGNOR TO STEPHEN G. TAYLOR, OF SAME PLAGE.

IMPROVEMENT IN BOlLEPt-FU PLNACES.

Specification forming part of Letters Patent No. 44,366. dated September 20, 1864.

To all 10710717, it may concern:

Be it known that I, THOMAS B. DAVIS, of Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvement in Steam-Boiler Furnaces; and I do hereby declare that the following, taken in connection with the drawings which accompany and form part of this specification, is a description of my invention, sufficient to enable those skilled in the art to practice it.

This invention relates to the introduction of steam into thc incandescent fuel of aste-amboiler furnace (or into the ash-pit just below said fuel) for aiding the combustion and heat of the fuel, the invention consisting in the peculiar arrangement of a steampipe and draft-passage for throwing steam and air into the ash-pit of the furnace.

Y Figure l denotes a front view, Fig. 2 a side elevation, and Fig. 3 a cross-section, of a portion ot' a furnace having my invention embodied therewith.

In the common method of forcing steam into the ash-pit of boiler-furnaces by extending a steam pipe directly into, and so as to open within, the ash-pit no uniformity' of beneticial result takes place, because the air which supports combustion is very imperfectly and uneveuly brought into contact with the jet of steam. An attempt has been made to regulate the introduction of the steam into the ash-pit and its action upon the air supplying combustion by commingling the air and steam outside ot' the ash-pit, and supporting the combustion entirely from the commingled air and steam, the ash-pit doors being closed, and the passage through or by the steampipes being the only communication for the draft. This arrangement is objectionable, because there is at times an excess of steam carried into the ash-pit, more than the fuel takes up, and such excess condenses upon the walls ofthe ash-pit and furnace, and soon causes a deposit of soot, injurious to the furnace and detrimental to the proper combustion ofthe fuel.

lt is the purpose of my invention to overcome these difficulties by so arranging the steam-pipe that the door ot' the ash or draft pit may be kept open or partially open, while the' steam is thrown upon a current of air in such manner that said current supports the comthrough one of the side Walls thereof, I make a passage, f, opening freely at one end :into the ash-pitand at the other into the external atmosphere. Into this passage Il lea'd a steam-pipe, g, said pipe encircling the outer end ot' the passage and ceiling around in a tapering coil as it extends through the passage into the ash-pit, as seen in the drawings. The inner surface of this coil I puncture with holes in such manner that the jets of steam issuing therefrom shall be thrown radially toward the center or axis of the coil, and also toward the ash-pit. By this arrangement, whether the ash-pit doors are open or not, the air to support combustion is drawn through the passage f as it is there heated by the steam from the pipe g, and, thus heated and moistened or vaporized by steam, it is dit'nsed throughout the ash-pit and imparts to the tire a high degree of vitality, while by having the ash-pit doors open an excess ot` steam is prevented, any surplus passing out ofthe ash pitdoors. The steam-blast through the passage f creates a draft through said passage, ratherthan through the ash-pit doors, While the steam at any time escaping through the doors e will indicate its excess to the tireman, who can thus regulate the amount introduced through the passage 'j'.

Although described as applied to a steamboiler, it will be evident that the invention is applicable to any other furnace into the draft or ash-pit of which a steam-pipe may be con ducted.

I claim- In combination with an ash-pit of a steamboiler furnace constructed with doors to open inthe usual manner, the passage f and steamcoil g, operating together in the manner and for the purpose substantially as set forth.

THOMAS B. DAVIS.

Witnesses:

F. GoULD, S. B. RIDDER. 

